scholarly journals R-spondin 2 mediates neutrophil egress into the alveolar space through increased lung permeability.

2019 ◽  
Author(s):  
Sergio Randell Jackson ◽  
Maria Fernanda De Mello Costa ◽  
Christopher Frances Pastore ◽  
Gan Zhao ◽  
Aaron I. Weiner ◽  
...  
Keyword(s):  
Neutrophil Migration ◽  
Fluorescein Isothiocyanate ◽  
Lavage Fluid ◽  
Permeability Barrier ◽  
Cell Content ◽  
Barrier Disruption ◽  
Lung Permeability ◽  
Balf Cell ◽  
Lung Vascular Permeability ◽  
Experimental Injury

Abstract Objective: R-spondin 2 (RSPO2) is required for proper lung morphogenesis. Our objective was to investigate whether RSPO2 is similarly important in homeostasis of the adult lung. Unexpectedly, we observed changes in neutrophil migration and lung vascular permeability in RSPO2-deficient (RSPO2-/-) mice compared to RSPO2 control (RSPO2+/+) mice, independent of experimental injury/challenge. Here we use multiple methods to quantify these observations to further understand how tonic RSPO2 expression regulates lung homeostasis. Results: Quantitative PCR (qPCR) analysis demonstrated significantly higher myeloperoxidase (MPO) expression in bronchoalveolar lavage fluid (BALF) cell content from RSPO2-/- mice compared to RSPO2+/+ mice. Immunocytochemical (ICC) analysis likewise demonstrated significantly more MPO+ cells in BALF from RSPO2-/- mice compared to RSPO2+/+ mice, confirming the increase of infiltrated neutrophils. We then assessed lung permeability/barrier disruption via Fluorescein isothiocyanate (FITC)-dextran instillation and found a significantly higher dextran concentration in the plasma of RSPO2-/- mice compared to identically treated RSPO2+/+ mice. These data demonstrate that RSPO2 may be crucial for lung barrier integrity and can facilitate an increase in neutrophil migration from circulation into alveolar spaces due to increased lung permeability/barrier disruption. Our studies suggest additional research is needed to evaluate RSPO2 in scenarios exhibiting either pulmonary edema or neutrophilia.

scholarly journals R-spondin 2 mediates neutrophil egress into the alveolar space through increased lung permeability.

2020 ◽  
Author(s):  
Sergio Randell Jackson ◽  
Maria Fernanda De Mello Costa ◽  
Christopher Frances Pastore ◽  
Gan Zhao ◽  
Aaron I. Weiner ◽  
...  
Keyword(s):  
Bronchoalveolar Lavage ◽  
Bronchoalveolar Lavage Fluid ◽  
Neutrophil Migration ◽  
Fluorescein Isothiocyanate ◽  
Lavage Fluid ◽  
Permeability Barrier ◽  
Gas Barrier ◽  
Barrier Disruption ◽  
Lung Permeability ◽  
Qpcr Analysis

Abstract Objective R-spondin 2 (RSPO2) is required for lung morphogenesis, activates Wnt signaling, and is upregulated in idiopathic lung fibrosis. Our objective was to investigate whether RSPO2 is similarly important in homeostasis of the adult lung. While investigating the characteristics of bronchoalveolar lavage in RSPO2-deficient (RSPO2-/-) mice, we observed unexpected changes in neutrophil homeostasis and vascular permeability when compared to control (RSPO2+/+) mice at baseline. Here we quantify these observations to explore how tonic RSPO2 expression impacts lung homeostasis. Results Quantitative PCR (qPCR) analysis demonstrated significantly elevated myeloperoxidase (MPO) expression in bronchoalveolar lavage fluid (BALF) cells from RSPO2-/- mice. Likewise, immunocytochemical (ICC) analysis demonstrated significantly more MPO+ cells in BALF from RSPO2-/- mice compared to controls, confirming the increase of infiltrated neutrophils. We then assessed lung permeability/barrier disruption via Fluorescein Isothiocyanate (FITC)-dextran instillation and found a significantly higher dextran concentration in the plasma of RSPO2-/- mice compared to identically treated RSPO2+/+ mice. These data demonstrate that RSPO2 may be crucial for blood-gas barrier integrity and can limit neutrophil migration from circulation into alveolar spaces associated with increased lung permeability and/or barrier disruption. This study indicates that additional research is needed to evaluate RSPO2 in scenarios characterized by pulmonary edema or neutrophilia.

Initial recruitment of neutrophils to alveolar structures in acute lung injury

1991 ◽  
Vol 70 (4) ◽  
pp. 1575-1585 ◽  
Author(s):  
G. C. Kindt ◽  
J. E. Gadek ◽  
J. E. Weiland
Keyword(s):  
Respiratory Distress Syndrome ◽  
Respiratory Distress ◽  
Bronchoalveolar Lavage ◽  
Bacterial Pneumonia ◽  
Bronchoalveolar Lavage Fluid ◽  
Distress Syndrome ◽  
Neutrophil Migration ◽  
Lavage Fluid ◽  
Neutrophil Influx ◽  
Lung Lymph

The adult respiratory distress syndrome and bacterial pneumonia are both characterized by an influx of neutrophils into the lung. The neutrophil has been implicated as having a “pathological” role in adult respiratory distress syndrome, in contrast to its role in bacterial pneumonia. We hypothesized that processes resulting in neutrophil recruitment to the lung are distinct, depending on whether the inflammatory stimulus arises in the intravascular or the alveolar compartment of the lung. Anesthetized sheep with lung lymph fistulas were utilized to access the three compartments of the lung relevant to studies of transpulmonary neutrophil migration. Serum, lung lymph, and bronchoalveolar lavage fluid were studied for neutrophil influx and chemotactic activity before and after administration of endotoxin by either an intravascular or inhaled alveolar route. Both groups developed significant neutrophil influx into the lymph and bronchoalveolar lavage fluid by 3 h postendotoxin. Those animals receiving intravascular endotoxin developed chemotactic gradients opposing neutrophil migration into the lung in contrast to animals receiving alveolar endotoxin, suggesting that neutrophil influx into the lung occurs by random migration.

scholarly journals Immunomodulating Effects of HMR 3004 on Pulmonary Inflammation Caused by Heat-Killed Streptococcus pneumoniae in Mice

1998 ◽  
Vol 42 (12) ◽  
pp. 3309-3312 ◽  
Author(s):  
Michel Duong ◽  
Marie Simard ◽  
Yves Bergeron ◽  
Nathalie Ouellet ◽  
Mélanie Côté-Richer ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Streptococcus Pneumoniae ◽  
Bronchoalveolar Lavage ◽  
Bacterial Pneumonia ◽  
Bronchoalveolar Lavage Fluid ◽  
Pulmonary Inflammation ◽  
Antimicrobial Properties ◽  
Fluorescein Isothiocyanate ◽  
Lavage Fluid ◽  
Lung Edema

ABSTRACT We investigated the influence of HMR 3004, a new ketolide antibiotic, on the pulmonary inflammation induced by heat-killed fluorescein isothiocyanate-labeled Streptococcus pneumoniae. HMR 3004 downregulated (P < 0.05) the pneumococcus-induced release of interleukin-6 (IL-6), IL-1β, and nitric oxide in bronchoalveolar lavage fluid. The drug limited (P < 0.05) neutrophil recruitment to lung tissues and alveoli but did not interfere with phagocytosis. HMR 3004 totally abrogated lung edema. By reducing inflammation in addition to possessing antimicrobial properties, HMR 3004 may participate in improving the outcome of bacterial pneumonia.

scholarly journals Nur77 limits endothelial barrier disruption to LPS in the mouse lung

2019 ◽  
Vol 317 (5) ◽  
pp. L615-L624 ◽  
Author(s):  
Ni Zhu ◽  
Guan-Xin Zhang ◽  
Bing Yi ◽  
Zhi-Fu Guo ◽  
Soohwa Jang ◽  
...  
Keyword(s):  
Cultured Cells ◽  
Serum Proteins ◽  
Fluorescein Isothiocyanate ◽  
Lavage Fluid ◽  
Endothelial Barrier ◽  
Pulmonary Vasculature ◽  
Mouse Lung ◽  
Orphan Nuclear Receptor ◽  
Protective Effects ◽  
Wide Range

Nur77 is an orphan nuclear receptor implicated in the regulation of a wide range of biological processes, including the maintenance of systemic blood vessel homeostasis. Although Nur77 is known to be expressed in the lung, its role in regulating pulmonary vascular functions remains entirely unknown. In this study, we found that Nur77 is expressed at high levels in the lung, and its expression is markedly upregulated in response to LPS administration. While the pulmonary vasculature of mice that lacked Nur77 appeared to function normally under homeostatic conditions, we observed a dramatic decrease in its barrier functions after exposure to LPS, as demonstrated by an increase in serum proteins in the bronchoalveolar lavage fluid and a reduction in the expression of endothelial junctional proteins, such as vascular endothelial cadherin (VE-cadherin) and β-catenin. Similarly, we found that siRNA knockdown of Nur77 in lung microvascular endothelial cells also reduced VE-cadherin and β-catenin expression and increased the quantity of fluorescein isothiocyanate-labeled dextran transporting across LPS-injured endothelial monolayers. Consistent with Nur77 playing a vascular protective role, we found that adenoviral-mediated overexpression of Nur77 both enhanced expression of VE-cadherin and β-catenin and augmented endothelial barrier protection to LPS in cultured cells. Mechanistically, Nur77 appeared to mediate its protective effects, at least in part, by binding to β-catenin and preventing its degradation. Our findings demonstrate a key role for Nur77 in the maintenance of lung endothelial barrier protection to LPS and suggest that therapeutic strategies aimed at augmenting Nur77 levels might be effective in treating a wide variety of inflammatory vascular diseases of the lung.

scholarly journals NSP4 Enterotoxin of Rotavirus Induces Paracellular Leakage in Polarized Epithelial Cells

2001 ◽  
Vol 75 (3) ◽  
pp. 1540-1546 ◽  
Author(s):  
Farideh Tafazoli ◽  
Carl Q. Zeng ◽  
Mary K. Estes ◽  
Karl-Erik Magnusson ◽  
Lennart Svensson
Keyword(s):  
Epithelial Cells ◽  
Tight Junction ◽  
Electrical Resistance ◽  
Fluorescein Isothiocyanate ◽  
Transepithelial Electrical Resistance ◽  
Permeability Barrier ◽  
Filamentous Actin ◽  
Specific Effects ◽  
Polarized Epithelia ◽  
Polarized Epithelial Cells

ABSTRACT The nonstructural NSP4 protein of rotavirus has been described as the first viral enterotoxin. In this study we have examined the effect of NSP4 on polarized epithelial cells (MDCK-1) grown on permeable filters. Apical but not basolateral administration of NSP4 was found to cause a reduction in the transepithelial electrical resistance, redistribution of filamentous actin, and an increase in paracellular passage of fluorescein isothiocyanate-dextran. Significant effects on transepithelial electrical resistance were noted after a 20- to 30-h incubation with 1 nmol of NSP4. Most surprisingly, the epithelium recovered its original integrity and electrical resistance upon removal of NSP4. Preincubation of nonconfluent MDCK-1 cells with NSP4 prevented not only development of a permeability barrier but also lateral targeting of the tight-junction-associated Zonula Occludens-1 (ZO-1) protein. Taken together, these data indicate new and specific effects of NSP4 on tight-junction biogenesis and show a novel effect of NSP4 on polarized epithelia.

scholarly journals The effect of induced sputum and bronchoalveolar lavage fluid from patients with chronic obstructive pulmonary disease on neutrophil migration in vitro

Medicina ◽  
2010 ◽  
Vol 46 (5) ◽  
pp. 315 ◽  
Author(s):  
Agnė Babušytė ◽  
Jolanta Jeroch ◽  
Rimantas Stakauskas ◽  
Kristina Stravinskaitė ◽  
Kęstutis Malakauskas ◽  
...  
Keyword(s):  
Bronchoalveolar Lavage ◽  
Bronchoalveolar Lavage Fluid ◽  
Neutrophil Migration ◽  
Lavage Fluid ◽  
Interleukin 8 ◽  
Induced Sputum ◽  
Chronic Obstructive ◽  
Healthy Individuals ◽  
Copd Patients

Objective. The aim of study was to investigate a chemotactic effect of induced sputum and bronchoalveolar lavage fluid on blood neutrophils in patients with chronic obstructive pulmonary disease (COPD) and healthy individuals. Material and methods. Forty-three smokers with COPD, 19 ex-smokers with COPD, 13 healthy smokers, and 17 healthy nonsmokers were recruited to the study. Neutrophils were isolated from peripheral blood of study individuals. For the same experimental conditions, pooled induced sputum and bronchoalveolar lavage fluid of 20 COPD patients were used. Neutrophil chemotaxis in vitro was performed in cell-transmigration chamber. Substances tested for chemoattraction (interleukin-8, induced sputum, bronchoalveolar lavage fluid directly or in addition to interleukin-8) were added to lower wells. Upper wells were filled with 2.5×106/mL of neutrophil culture and incubated for 2 hours. Migration was analyzed by flow cytometry. Results. Interleukin-8 (10–100 ng/mL) induced a dose-dependant neutrophil migration in all the groups. Only 100 ng/L of interleukin-8 induced more intensive chemotaxis of neutrophils from COPD smokers as compared to ex-smokers (P<0.05). Such difference between healthy individuals was obtained using 30 ng/mL of interleukin-8 (P<0.05). Induced sputum/interleukin-8 (10–100 ng/mL), as well as induced sputum directly, induced neutrophil migration (P<0.05). Chemotaxis of neutrophils isolated from COPD patients and healthy nonsmokers did not depend on additional interleukin-8 concentration. Bronchoalveolar lavage fluid/interleukin-8 (30–100 ng/mL) induced more intensive migration of neutrophils from COPD patients than bronchoalveolar lavage fluid (P<0.05) alone. Conclusions. Migration of neutrophils isolated from patients with COPD was more intensive compared to healthy individuals. Induced sputum and bronchoalveolar lavage fluid directly and with addition of interleukin-8 stimulated chemotaxis, and it was higher in neutrophils from COPD patients. Migration of neutrophils did not depend on smoking status.

scholarly journals Anti-Inflammatory Effects of Ellagic Acid on Acute Lung Injury Induced by Acid in Mice

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Daniely Cornélio Favarin ◽  
Maxelle Martins Teixeira ◽  
Ednéia Lemos de Andrade ◽  
Claudiney de Freitas Alves ◽  
Javier Emilio Lazo Chica ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Ellagic Acid ◽  
Neutrophil Migration ◽  
Lavage Fluid ◽  
Positive Control ◽  
Oral Route ◽  
Dexamethasone Treatment ◽  
Acid Aspiration ◽  
Anti Inflammatory

Acute lung injury (ALI) is characterized by alveolar edema and uncontrolled neutrophil migration to the lung, and no specific therapy is still available. Ellagic acid, a compound present in several fruits and medicinal plants, has shown anti-inflammatory activity in several experimental disease models. We used the nonlethal acid aspiration model of ALI in mice to determine whether preventive or therapeutic administration of ellagic acid (10 mg/kg; oral route) could interfere with the development or establishment of ALI inflammation. Dexamethasone (1 mg/kg; subcutaneous route) was used as a positive control. In both preventive and therapeutic treatments, ellagic acid reduced the vascular permeability changes and neutrophil recruitment to the bronchoalveolar lavage fluid (BALF) and to lung compared to the vehicle. In addition, the ellagic acid accelerated the resolution for lung neutrophilia. Moreover, ellagic acid reduced the COX-2-induced exacerbation of inflammation. These results were similar to the dexamethasone. However, while the anti-inflammatory effects of dexamethasone treatment were due to the reduced activation of NF-κB and AP-1, the ellagic acid treatment led to reduced BALF levels of IL-6 and increased levels of IL-10. In addition, dexamethasone treatment reduced IL-1β. Together, these findings identify ellagic acid as a potential therapeutic agent for ALI-associated inflammation.

scholarly journals Inhibition of Prostaglandin F2α Receptors Exaggerates HCl-Induced Lung Inflammation in Mice

2021 ◽  
Vol 22 (23) ◽  
pp. 12843
Author(s):  
Toko Maehara ◽  
Ko Fujimori
Keyword(s):  
Umbilical Vein ◽  
Lung Surfactant ◽  
Neutrophil Migration ◽  
Prostaglandin F2α ◽  
Lavage Fluid ◽  
Clinical Feature ◽  
Lung Edema ◽  
Induced Expression ◽  
Respiratory Dysfunction

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are severe respiratory disorders that are caused by aspiration, sepsis, trauma, and pneumonia. A clinical feature of ALI/ARDS is the acute onset of severe hypoxemia, and the mortality rate, which is estimated at 38–50%, remains high. Although prostaglandins (PGs) are detected in the bronchoalveolar lavage fluid of patients with ALI/ARDS, the role of PGF2α in ALI remains unclear. We aimed to clarify the role of PGF2α/PGF2α receptor (FP) signaling in acid-induced ALI using an FP receptor antagonist, AL8810. Intratracheal injection of hydrochloric acid (HCl) increased neutrophil migration into the lungs, leading to respiratory dysfunction. Pre-administration of AL8810 further increased these features. Moreover, pre-treatment with AL8810 enhanced the HCl-induced expression of pro-inflammatory cytokines and neutrophil migratory factors in the lungs. Administration of HCl decreased the gene expression of lung surfactant proteins, which was further reduced by co-administration of AL8810. Administration of AL8810 also increased lung edema and reduced mRNA expression of epithelial sodium channel in the lungs, indicating that AL8810 reduced fluid clearance. Furthermore, AL8810 also increased lipopolysaccharide-induced expression of adhesion molecules such as intracellular adhesion molecule-1 and E-selectin in human umbilical vein endothelial cells. These results indicate that inhibition of FP receptors by AL8810 exacerbated HCl-induced ALI.

Leukotriene B4-induced neutrophil-mediated endothelial leakage in vitro and in vivo

1991 ◽  
Vol 71 (4) ◽  
pp. 1322-1330 ◽  
Author(s):  
S. Rosengren ◽  
A. M. Olofsson ◽  
U. H. von Andrian ◽  
E. Lundgren-Akerlund ◽  
K. E. Arfors
Keyword(s):  
Umbilical Vein ◽  
Neutrophil Migration ◽  
Fluorescein Isothiocyanate ◽  
Leukotriene B4 ◽  
Vascular Leakage ◽  
Neutrophil Granulocytes ◽  
Vitro Assay ◽  
Umbilical Vein Endothelial Cells

The vascular leakage of macromolecules seen in several models after application of leukotriene B4 (LTB4) is mediated by neutrophil granulocytes. We describe here an in vitro assay for this event. Human umbilical vein endothelial cells were grown on polycarbonate filters separating luminal and abluminal compartments of fluid. Both clearance rate of fluorescein isothiocyanate albumin and neutrophil migration through the endothelial monolayer were increased when LTB4 (10–100 nM) was added to the abluminal compartment. However, if LTB4 was instead added to the luminal compartments together with the neutrophils, no migration or change in clearance could be detected. These findings were confirmed in vivo in the cheek pouches of anesthetized hamsters, where extravascular application of LTB4 induced intravascular adhesion of neutrophils, accompanied by neutrophil-dependent vascular leakage. On the other hand, intravascular deposition of LTB4 with micropipettes induced adhesion of leukocytes but no leakage. In conclusion, the presence of neutrophils adhering to endothelium does not necessarily imply the development of neutrophil-mediated vascular leakage. Instead, the leakage appears connected to the process of neutrophil chemotaxis.

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